1. Field of the Invention
The present invention relates to a video printer, and more particularly to a video printer of the type which is adapted to receive a picture signal from a video tape recorder having a camera incorporated therein, for example, and print a desired still image while developing the image signal to a monitor device.
2. Description of the Related Art
For example, when images captured using a video tape recorder having a camera incorporated therein such as an 8 mm video camera, (hereinafter simply referred to as camera recorder) are reproduced on a video monitor device, one who desires that some of the images displayed on the monitor device be printed uses a video printer.
The conventional video printer has a video input terminal to which a reproduced signal is received from a camera recorder and a video output terminal from which the reproduced signal is delivered to a monitor device. Between the input and output terminals, there are provided a line over which the received, reproduced signal from the camera recorder is directly transmitted to the monitor device, and another line to which coupled is a frame memory in which some frame of signal involved in the reproducing signal is stored. If it is desired that a picture signal is stored in the frame memory, a button or key for taking signal in or freeze button, which is provided on the outer surface of the printer casing, is depressed, so that the associated frame of picture signal is written into the frame memory. In order to monitor a picture represented by the picture signal stored in the frame memory, a frame selector button is depressed, so that instead of the reproduced, movie signal representative of movie images from the camera recorder, data representative of a still image involved in the frame memory is delivered to the monitor device. If the still image thus displayed is desired one to be printed, a print button is depressed to read out the picture signal from the frame memory to a printer section, which will in turn print an image based on the picture signal.
Further, as an especial function of the video printer, there is known a so-called index printing in which a plurality of frames are reduced into a single, index frame and then printed. In this case, a mode selector key or button is operative to select an indexing mode in which the freeze button is depressed, at the moment a desired frame of image is reproduced, in a similar way as mentioned above, so that that frame of image is stored. Then, advancing the reproducing procedure, a successive frame of image is stored in the same key operation. This operation is sequentially repeated for a plurality of frames desired so that a desired number of frames of picture signal are stored in the frame memory. Each of the picture signals stored in the memory is thinned to one-sixteenth by a signal processing circuit such as a digital signal processor, and sequentially stored in a memory for use in the index printing. The plurality of images of picture signal thus thinned and stored in the memory are, in response to the print button depressed, printed in the form of a single frame of index image or multiple image on a sheet of print paper.
However, in the prior art mentioned above, while a desired, full frame of image is printed in the video printer, a playback operation on the tape is continuously performed at the camera recorder. Thus, when the monitor screen is switched to a camera recorder image, or movie image, after the printing is terminated, the playback of camera recorder images has often extensively proceeded from the image just subjected to the printing. Consequently, if the operator wishes to print or observe an additional field recorded in a portion of the tape that has already passed over, then he or she will be obliged to rewind the tape. In order to avoide that difficulty to print a desired image, one usually manipulates the video printer in such a manner that he or she depresses the freeze button of the printer to take a picture signal in, and the stop button of the camera recorder to temporarily halt the movie playback, and thereafter carries out the printing operation on the video printer. Therefore, in the case where one wishes to print a plurality of frames of image, he or she would be obliged to inherently manipulate a lot of operational keys on the different devices, that is, the camera recorder and the printer. Specifically, the operator depresses on the various devices in sequence, for example, the playback button of the camera recorder, the freeze button of the printer, the stop button of the camera recorder, and the field selector and print keys of the printer, and returns to the playback button of the camera recorder. Thus, the prior art system involves the difficulty that the key operation is troublesome.
Further, according to the prior art mentioned above, when the operator whishes to make an index frame, he or she has to watch the monitor screen while playing a video tape back, and thus it would take a remarkable time to print one index frame. In order to reduce such an extended period of time, it could be considered that the operator manipulates the camera recorder to feed a tape forward and pause at a predetermined interval to take images in at the intervals, so that the index frame is formed in a rather simpler way. In this case, the operator watches the counter of the camera recorder to allow the tape to be fed forward to a predetermined position. At the time the tape reaches the desired position, the operator makes the camera recorder playback in a regular reproducing mode, and when the tape speed becomes constant, he or she depresses the freeze button to take the image in. Subsequently, the operator opearates the recorder to feed the tape forward again, and when the tape reaches a predetermined position, the operator makes the camera recorder playback in a regular reproducing mode again, and depresses the freeze button to take another image in. The repetition of this operation makes it possible to load the printer with a plurality of images and thus to build the index frame in a shorter period of time. In this case, however, many operations not only on the printer but also the camera recorder are carried out. Therefore, when the operator wishes to form an index frame, he or she would be obliged to manipulate the separate devices, namely, the camera recorder and the printer. Thus, the prior art system involves the problem that the operation on the different devices is also troublesome when forming an index frame.